5 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Hot Springs | 1 | 3,660 | 3,399 | 1.44% | 843 | 4 | City |
| Edgemont | 2 | 766 | 729 | 0.92% | 554 | 1 | City |
| Oelrichs | 3 | 127 | 119 | 0.79% | 348 | 0 | Town |
| Provo | 4 | 35 | 32 | 2.94% | 1 | 36 | Township |
| Argentine | 5 | 18 | 17 | 0% | 1 | 36 | Township |
Hot Springs is the largest city in Fall River County, with a population of 3,660.
Argentine is the smallest city in Fall River County, with a population of 18.
There are 5 cities in Fall River County, South Dakota.